With the increasing use of audio devices, increase of the ratio of the elderly population, and frequent exposure to noisy environments, the hearing-impaired population is increasing. This is spurring the development of electronic devices (e.g., hearing aid) equipped with various functions for assisting hearing-impaired persons.
Typically, hearing-impaired persons may have difficulty in perceiving sounds correctly in a part or the whole of a frequency band. A hearing aid is designed to compensate for a hearing loss by amplifying sounds in a part or the whole of the frequency band audible to the human ear. Conventional electronic devices (e.g., hearing aid) are designed to shift a high frequency band signal downwards in frequency for a high frequency band hearing-impaired user. In this case, the user may hear the unperceivable high frequency band sound within the user's perceivable frequency range, but there is a difference between the real sound and the sound perceived by the user because of a change of signal waveform.